Chemical engineer Askwar Hilonga wants to be a billionaire - by saving a billion lives. Growing up in rural Tanzania, life was hard. His mother and father didn't go to school and he suffered from water-borne diseases throughout his childhood from drinking contaminated water. Askwar wanted to use his education to help his community and, using his expertise in nanotechnology, he has developed a water filtration system and a network of water purification stations around Africa. He tells his story to Trevor Cox in the fourth episode of Inventive Podcast. Novelist Sarah Franklin, who runs the ‘Short Stories Aloud’ events and is also a judge on the Costa Short Story Award, has written a moving short story based on Askwar's life and work. See acast.com/privacy for privacy and opt-out information.